Books are key to understanding the world and participating in a democratic society.

The universe is not required to be in perfect harmony with human ambition.

Religions contradict one another-on small matters, such as whether we should put on a hat or take one off on entering a house of worship, or whether we should eat beef and eschew pork or the other way around, all the way to the most central issues, such as whether there are no gods, one God, or many gods.

Scientists make mistakes. Accordingly, it is the job of the scientist to recognize our weakness, to examine the widest range of opinions, to be ruthlessly self-critical. Science is a collective enterprise with the error-correction machinery often running smoothly.

Even today the most jaded city dweller can be unexpectedly moved upon encountering a clear night sky studded with thousands of twinkling stars. When it happens to me after all these years it still takes my breath away.

The sacred truth of science is that there are no sacred truths.

To live in the hearts of others is to never die in those we leave behind.